Using an e-mail address to sign up for things twice?

[jackofalltrades]

Hi all,
I was wondering if anybody knows of a way I can sign up to web sites with one e-mail address, and then make another account with the same e-mail address, but written differently so it is undetected.
I vaguely remember hearing you can put a . before it or something but I'm not sure, so if anybody knows this or can at least point me in the right direction I would be so so grateful.
Thanks,
Jack

[SiM]

With gmail you can do if your email is blabla@gmail.com] you will also receive emails from:
1) blabla+*@gmail.com where * can be any valid email string of characters.
2) bla.bla@gmail - add a "." anywhere the email so bla.bla@gmail would work and b.labla@gmail would also work.
3) blabla@googlemail.com goes to the same account too

[jackofalltrades]

Sorry, I should of added that in the OP; it's not a gmail account, it's a university e-mail address. And I can't use a gmail account for this purpose. Thank you for trying though, still grateful

[SiM]

Well it depends on your uni then... We have 2 emails at warwick one is name@warwick, the other is usercode@smail.warwick
we can only send from name@warwick, but the real account is usercode@smail